Rock drill



G. LEE

Rocx DRILL Filed April 16, 1926 Aug. 24

I275 ATIORNEY.

Patented Aug". 24, 1926.

UNITED STATES 1,597,413 PATENT OFFICE.

GORDON LEE, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND COMPANY,I

OEJERSEY' CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

ROCK DRILL.

Application filed April 16, 1926. Serial No. 102,486.

This invention relates to rock drills, but

.' rock drill strong and durable.

Other objects will be in part obvious and in part pointed outhereinafter.

The invention consists of the combination 'of elements and arrangementof parts having the general mode of operation substantially ashereinafter described and more particularly pointed out in the appendedclaims and illustrated in the accompanying vdrawings, in which" i v IFigure 1 is an elevation, in section, of a rock drill of the hand heldtype equipped withv acontrolling means constructed in accordance withthe practice of the invention,

Figure 2 is a view of one of the grip portions, partly in section,illustrating one of the positions which the handle sleeve may assume inpractice, and

Figure 3 is a view similar to Figure 2 illustrating the osition of thehandle sleeve when the valve is fully open.

Referring to the draw-ings, the invention is shown' embodied in a rockdrill of the 1 hand held type in which a cylinder A is provided with afree exhaust portvB. Within the cylinder A is arranged. a reciprocatoryhammer piston C having a rearw ardly reduced extension D reciprocable ina bore E formed in the rearward portion of the cylinderA. f

A back head F forms a closure for the rearward end of the cylinder-andthe forward. end of the cylinder is sealed in this instance by means ofa front cylinder washer G interposed between'the front end of thecylinder and a front head'H. In addition to forming a closure for thefront end of the cylinder A, the washer G also acts as a guide for ananvil block J ada ted to transmit the blows of the piston to a drillsteel K supported by thefront' head H. The parts comprising the casingof the rock drill, namely, the cylinder A, the back head F, the fronthead H, and the front cylinder washer G may be held or clamped inoperative position with respect to each other Y in any suitable manner,preferably by means of the usual side bolts, (not shown).

Pressure fluid for actuating the percussive element of the rock drillmay be conveyed from a' source of supply throu h a conduit L secured tothe back head F y means of a suitable connection 0. Such pressure fluidmay pass to the rearward end of the bore E through a passage P.

The piston C illustrated in the drawings is of. the type which may beconstantly exposed to pressure fluid at the'rearward end of theextension D. In this instance the extension D constitutes the means fordistributing the pressure fluid to the ends of the cylinder A.Accordingly, a passage" Q, leading from the rearward rtion of-the bore Ecommunicates at its ti'bnt end with the forward portion of the bore Efor admitting pressure fluid to the rearward end of the cylinderto'impel the piston C forwardly. The extension D is provided with areduced portion B so that when the piston approaches its rearwardlimiting position the front endof the passage Q will be uncovered toadmit pressur e fluid to the rearward end of the cylinder.

The admission of pressure fluid to the front end of the cylinder A is inthis in: stance effected through a passage S leading from the front endof the cylinder to communicate with the bore E at a point rearwardly ofthe forward end of the assage Q. The passage S like the passage (5 isalso controlled by the extension D and is so positioned that at aboutthe time the hammer .piston delivers its blow to the anvil block J,

pressure fluid will flow through the passage S into the front end of.the cylinder for returning the piston.

In accordance with the practice. of the invention a pair of lateralgripportions T and U are formed integrally with the back head to serve as ameans for supporting the rock drill and for holding it to the work. Thegrip portion U is preferably of somewhat smaller diameter than theopposed H to receive rotatably a-handle sleeve The sleeve V has smoothunbroken outer peri-' limiting endwise movement of the sleeve V ,in onedirection. Any suitable means may be provided for preventingvaccidental, re-

moval of the sleeve V from the grip U. .A

convenient means for accomplishing this isillustrated in the drawings inwhich awasher Y of substantially, the same diameter as the sleeve abutsthe outer end of the sleeve and is held inposition by a bolt Z screwedinto the end of the grip U. i

The-admission of pressure fluid conveyed to the backhead F through theconduit L is controlled by a throttle valve 6 in the back head. Thethrottle valve b may be located hold the valve closed.

Suitable means are provided to limit the rotative movement of the sleeveV on the grip portion U. To that end faces f and g are formedlongitudinally of thesleeve ada'cent the ends of the cam face W. In thepresent instance the face f is adapted to contact withthe side of thepush rod (1 when the sleeve V is rotated to a position to permit thevalve 6 to rest on its seat, and the face 9 is 'ada ted to contact withthe side of the push re (1 only when the valve 1) is fully open. Ifdesired, a flat face it may be formed at that end of the cam face Wnearest the face 9 so that when the valve 6 has been opened to widelimits the sleeve V will be held against rotation by the action of thespring e.

substantial In the operation of the device, whenever it is desired toadmit pressure fluid into the clym linder A for reciprocating the pistonO, t e sleeve V may berotated in a counterclockwise direction as viewedfrom the right hand side of the figures. Such rotation of the sleevewill cause the cam sunface W to ride on the outer end of the push rod (1and will force the valve b from its seat. Continned rotation in thisdirection of the sleeve V; will carry the flat surface It to cont-actwith the end of the push rod 11 and the sleeve V may then be released bythe operator and will be held securely against rotation by the pressureof the spring e. e

The advanta es of this invention reside chiefly in the act that theperimetric surface of the grip portions T and U may remain y unbrokenthroughout their lengths. This construction renders these 'p portionsstrong and eliminates the unue breakage thereof which frequently occursin drills of this type. By means ofthe controlling 'mechanismhereinbefore de-- able advantageof this construction is that .theoperator -may at all times apply full pressure tothe handle of the drillwith both hands without necessitating the frequent release of one of thegrips, or a change of position of his hands, for the purpose ofmanipulating the pressure fluid controlling element.

I claim: a v

1. In a fluid actuated rock drill, the combination of a cylinder, areciprocatory hammer piston in the cylinder, a back head for thecylinder, grip portions on the back head forming a handle, a throttlevalve in the back head for controllin the admission of pressure fluidto'the cyhnder, an extension on the valve, a rotatable handle sleeve onone of the grip portions said sleeve having smooth unbroken outerperimetric surfaces throughout its length, and a cam on the end face ofthe sleeve to abut the extension for opening and closingthe valve.

2. In a fluid actuated rock drill, the combination of a cylinder, areciprocatory hammer piston in the cylinder, aback head for thecylinder, grip portions on the back head forming a handle, a throttlevalve located transversely in the back head for controlling theadmission of pressure fluid to the cy.inder, an extension on the valve,a rotatable handle sleeve on one 6f the grip portions, a cam on theinner end face of the sleeve to abut the valve extension for opening andclosing the valve, a shoulder on the back head to limit endwise movementof the sleeve in an inward direction, and a bolt in the handle to holdthe sleeve against re moval from the .handle.

. 3. In a fluid actuated rock drill, the combination of a cylinder, areciprocatory hammer piston in the cylinder, a back head for thecylinder, lateral grip portions on the back head forming a handle formanipulating the rock drill, said grip portions having smooth unbrokenperimetric surfaces, a throttlevalve located diagonally in the back headfor controlling the admission or pressure fluid to the cylinder, anextension on the valve extending through the back'head into the handle,a sleeve rotatable on.the handle, a cam on the inner end face of thesleeve to abut the valve extension for unseating the valve, a shoulderon the back head for limiting-endwise movement of the sleeve inarr-inward direction, means for preventing removal of the sleeve fromthe handle, a spring for closing the valve upon release of the sleeve.

Intestimony whereof I have signed this specification.

GORDON LEE.

